There are several procedures available to patients with degenerative spine conditions. For example, Anterior Lumbar Interbody Fusion (“ALIF”) has been performed by surgeons since the 1950's. In an ALIF procedure, the disc space is fused by approaching the spine through the abdomen. In the ALIF approach, a three-inch to five-inch incision is made on the left side of the abdomen and the abdominal muscles are retracted to the side. Since the anterior abdominal muscle in the midline (rectus abdominis) runs vertically, it does not need to be cut and easily retracts to the side. The abdominal contents lay inside a large sack (peritoneum) that can also be retracted, thus allowing the spine surgeon access to the front of the spine without actually entering the abdomen. There is also a less popular transperitoneal approach that accesses the spine through the abdomen. This adds a lot of unnecessary morbidity to the procedure and therefore is used much less often.
Another technique is called Posterior Lumbar Interbody Fusion (“PLIF”). In the PLIF approach, the spine is accessed through a three-inch to six-inch long incision in the midline of the back and the left and right lower back muscles are stripped off the lamina on both sides and at multiple levels. After the spine is approached, the lamina is removed, which allows visualization of the nerve roots. The facet joints, which are directly over the nerve roots, may then be undercut to give the nerve roots more room. The nerve roots are then retracted to one side and the disc space is cleaned of the disc material. A bone graft, or an interbody cage, is then inserted into the disc space and the bone grows from vertebral body to vertebral body.
Still another procedure is a Transforaminal Lumbar Interbody Fusion (“TLIF”). By removing the entire facet joint, visualization into the disc space is improved and more disc material can be removed. It should also provide for less nerve retraction. Because one entire facet is removed, it is only done on one side. Removing the facet joints on both sides of the spine would result in too much instability. With increased visualization and room for dissection, a larger implant and/or bone graft can be used. Although this has some improvements over a PLIF procedure, the anterior approach, in most cases still provides the best visualization, most surface area for healing, and the best reduction of any of the approaches to the disc space.
There are other approaches know in the art, as well. For instance, Direct Lateral Interbody Fusion, Axial Lift using a transsacral approach, and the like. Additionally, there are similarly pluralities of methods for correcting degenerative issues with the cervical spine. Those skilled in the art will appreciate that these and other known procedures have benefits, as well as disadvantages. As such, more beneficial approaches in the art are needed.